let p1 = new Promise((resolve) => {
    setTimeout(() => {
        console.log('执行p1');
      resolve('P1 fetch 请求成功')
    },5000)
 })
 let p2 = new Promise((resolve,reject) => {
    setTimeout(() => {
        console.log('执行p2');
        reject('P2 fetch 请求失败')
    },2000)
 })
 let p3 = new Promise((resolve) => {
    setTimeout(() => {
        console.log('执行p3');
        resolve('P3 fetch 请求成功')
    },1000)
 })

 Promise.all([p1,p2,p3]).then((res)=>{
    console.log("已经获取到合适的结果了===",res);
 }).catch((e)=>{
     console.log("发生异常=",e);
 })